Objectives: This study was designed to validate the Cardiac Depression Scale (CDS) in a UK cardiac population.
Method: A battery of questionnaires (the Medical Outcomes Study Short-Form 36 [SF-36] Health Survey, the Beck Depression Inventory [BDI], the Hospital Anxiety and Depression Scale [HADS] and the Cardiac Depression Scale [CDS]) was mailed to 487 individuals with coronary heart disease (CHD) recruited from cardiac support groups. The process was repeated on a subsample of 80 participants four-six weeks later for the purpose of test-retest analysis.
Results: The response rate from the first administration was 81% and from the test-retest subsample 54%. Factor analysis revealed a one-factor solution with a high internal reliability (Cronbach's α = 0.93) and an acceptable test-retest reliability (0.79). Concurrent validation against the SF-36, BDI and HADS demonstrated strong correlations.
Conclusions: The CDS is both a reliable and sensitive instrument for measuring depression in cardiac patients.